That small plug is called "ear nail", PT950 ear nail. Its material is platinum, so the earrings it follows must also be platinum.

In contrast, it is a "Liu Fu" brand, which is also a well-known brand. It buys platinum earrings without non-platinum earrings.

You can go to some jewelry processing or a specialty store in Liu Fu to buy one. It won't be expensive. I don't know what your style is. Relatively speaking, it should be 0.2 to 0.4 grams of earrings.

It is recommended to go to the processing factory to buy it. By contrast, going to the shopping center is much cheaper.